Many types of cartons for packaging articles are known. However, these cartons have not been suitable for use when an automatic closing bottom carton is desired, such as a carton which can be folded flat and then loaded onto normal filling equipment. The preparation of such a carton, particularly an oval shaped carton, where the bottom of the flat folded carton automatically erects during filling, generally requires several steps.
U.S. Pat. No. 1,184,956 (Hoppke) discloses a pastry cup having a segmental member with its opposite ends secured together to form a shell. Two bottom members are arranged to fit within the shell at the lower end and are secured together and two necks integrally connect the bottom members within the shell and are located within the shell opposite each other. U.S. Pat. No. 1,733,674 (Schleicher) discloses a box having an inside bottom-forming sheet with a continuously curved edge. A side wall is provided for the box having an elongated strip with V-shaped tongues extending from one edge and bent inwardly and glued against the under side of the bottom sheet. U.S. Pat. No. 1,803,239 (Deane) discloses a carton constructed of a blank having a main portion shaped to form a cylindrical hollow body. A pair of circular portions are provided with one edge of the main portion forming end closure members consisting of an inner closure member and an outer flanged closure member for one end of the hollow body. U.S. Pat. No. 3,101,167 (Styler) discloses an automatic bottom hexagonal carton erectable by a single application of compressive forces on the edges of the carton when in a collapsed condition. A bottom flap is secured to the bottom edge of a first side panel and is creased at its mid-portion so that it may be folded back upon itself. When the bottom flap unfolds during the application of opening forces to the collapsed container, the flap pulls the bottom dust flap into position. U.S. Pat. No. 3,790,064 (Kramer) discloses a carton with an automatic lock bottom construction. The carton has four main panels hinged together and is erectable from a collapsed condition into a locked erected condition. The lock means is a bottom lock flap with a projecting finger-like tab. During the erection of the carton, secured hook tabs and adjacent rectangular projections lift each other and unfold from against the main panels. U.S. Pat. No. 3,899,124 (Desmond et al.) discloses a collapsible carrying carton adapted to be brought from a collapsed condition to an erected condition by the application of pressure against two opposed corners. The bottom closure includes include a flat, unscored, bottom panel attached at one edge to a lower edge of a related major side wall and having a recess for interlocking with a corresponding recess in the bottom panel of the other closure flap of the first pair when the carton is in erected condition. U.S. Pat. No. 4,109,848 (Kipp et al.) discloses a tubular carton formed from a cut and scored blank of paperboard. A recessed, concavely depressed bottom wall is formed from two overlapping bottom panel portions secured to each other. The side wall has remote side edges secured to each other in an overlapped relation to form a tubular structure collapsible into a substantially flat configuration. U.S. Pat. No. 4,428,500 (Kohler) discloses a collapsible, automatically erectable, liquid-tight tray. The tray has an outer shell formed from a unitary blank of foldable paperboard and a pair of opposed side wall panels joined to each other at corresponding side edges to form, when in the erected position, a tubular structure open at the top. U.S. Pat. No. 4,856,705 (Carr et al.) discloses an automatically-operating bottom structure for a collapsible container to be selectively moved between a folded-flat condition and a fully-expanded condition. Interlock means are provided for interlocking the bottom flaps when the container is in the fully-expanded condition. When the container is moved from the folded-flat condition to the fully expanded condition, a band will prevent the flaps from moving relative to their associated first panels. U.S. Pat. No. 5,484,100 (Rigby) discloses a tapered, hexagonal paperboard container having two paperboard bottom panels and six paperboard side panels connected to each other to form a tapered, hexagonal container. U.S. Pat. No. 5,630,543 (Dugan) discloses a bulk bin box having a unitary piece of cardboard folded into an octagonal box having a top portion and a bottom portion and two tabs on opposite sides of the box with each tab having a slot. Each tab slot simultaneously and continuously intermeshes with the other tab whereby no action other than opening the box is necessary to erect the box. U.S. Pat. No. 5,669,549 (Robertson) discloses a container having a longitudinal axis for storing and packaging dry, semi-dry or liquid goods. The container has a closed bottom and an upstanding sidewall wrapped about the longitudinal axis of the container and extending from the closed bottom to form a storage cavity. U.S. Pat. No. 5,669,550 (Klemme et al.) discloses a container having a longitudinal axis for storing and packaging one or more dry, semi-dry and/or liquid goods. The container has a closed bottom and a continuous sidewall wrapped about the longitudinal axis and extending upwardly from the closed bottom to an upper rim. U.S. Pat. No. 5,816,483 (Gasper) discloses a container to be selectively moved between a folded condition and an expanded condition. Panels are arranged in opposing pairs when the container is in an expanded condition and first and second sections are disposed with one another and with their respective panels so as to be parallel to one another when the container is in a folded condition and co-planar to one another when the container is in the expanded condition. U.S. Pat. No. 5,893,458 (Sisk) discloses a carton having a top closure, several side panels, several auto-bottom panels each connected to a bottom edge of one of the side panels, and several spaced panels connected to some of the auto-bottom panels. When the carton is erected, the auto-bottom panels form a generally planar bottom of the carton, and the spacer panels extend generally axially into the carton from the bottom to form a two-dimensional support base for holding an object at a location spaced above the bottom of the carton.